The Active Fibre Composite (AFC) has been the subject of much interest as a smart technology that can be embedded into host structures for adaptive shape control and structural health monitoring. The electromechanical performance of these devices has been extensively studied, although the structural properties have received little attention. Knowledge of the mechanical performance of the AFC is essential to prevent loss of performance and failure. Experimentally measured tensile strengths of PZT fibreepoxy composites were found to contradict the behaviour predicted by simple composite theory. It has been shown that the selection of appropriate matrix material is an essential factor in controlling the failure mode of active composites.